I see a QuickBooks ID field in most tables – what is the purpose of these fields?

Most tables that upload to QuickBooks Online will contain a “QuickBooksID” field named:

_kf_QuickBooksID

These fields store the QuickBooks Online unique identifier for each Customer, Vendor, Invoice, Purchase Order etc that you upload to QuickBooks Online or download from QuickBooks Online.

These operate in a similar way to a primary key field does in FileMaker. If there is a value in these fields that means that the Customer, Invoice etc has previously been uploaded (or downloaded from QuickBooks Online) – i.e. that FileMaker record also exists in QuickBooks Online. When uploading to QuickBooks Online if the “QuickBooks ID” field is empty a new record will be created in QuickBooks Online, otherwise the QuickBooks Online record that matches the “QuickBooks ID” field will be updated.

N.B. as these QuickBooks ID values should be unique make sure when you duplicate an Invoice, Customer, Bill etc that you clear out the value in these QuickBooks ID fields otherwise you will run into issues when uploading as it will be attempting to update that record in QuickBooks Online that matches the value in the QuickBooks ID field.